Effect of Supplemental Intake of Omega-3 Polyunsaturated Fatty Acids on the Rate and Complexity of Spontaneously Occurring Ventricular and Supraventricular Arrhythmias in Patients With Implantable Cardioverter Defibrillator (ICD) - A Randomized Clinical Trial

Effect of Supplemental Intake of Omega-3 Polyunsaturated Fatty Acids on the Rate and Complexity of Spontaneously Occurring Ventricular and Supraventricular Arrhythmias in Patients With Implantable Cardioverter Defibrillator (ICD) - A Randomized Clinical Trial

We hypothesize that oral supplementation with omega-3 PUFA will decrease occurrence of arrhythmic events among post-MI, ICD recipients.

This is a randomized, placebo-controlled, crossover, double- blind interventional study. Patients will receive 3.6 g of EPA and DHA fish oil and placebo oil for 6 months, randomly, in a crossover design, with a four month washout period between treatments. Randomization will be stratified by ejection fraction (≤ 35% or > 35%), and the type of the index arrhythmia (VT - spontaneous or inducible by electrophysiologic study (EPS), versus other - VF, SCD, Primary prevention - MADIT II). Ischemia severity was chosen to be evaluated by Single Photon Emission Computed Tomography (SPECT) during stress (dipyridamol infusion). Subcutaneous adipose-tissue biopsy, a biomarker considered the gold-standard for the objective assessment of long-term habitual dietary intake of fish and marine omega-3 PUFA (EPA and DHA) will be obtain. Compliance will be monitored by counting returned capsules or bottles and by measuring the omega-3 PUFA composition in red blood cells (RBC). Three different types of questionnaires will be used in this trial to obtain more information as to the additional potential benefit of omega-3 PUFA supplementation: The newly Israeli Food Frequency Questionnaire (FFQ) will be used to examine dietary intake of other nutritional habits/patterns and its relationship to the study outcomes. The Hebrew language SF-36 health survey will be used to examine general health status. The Back questionnaires will be use to examine possible beneficial effects of fish oil supplementation on depressive symptomatology.

Atrial arrhythmia and non-sustained ventricular arrhythmia (non-sustained VT or ventricular premature complex (PVC)) as documented by ICD memory or 24 hour ECG (Holter) recording.

Whether omega-3 PUFA supplementation exerts different effects according to ischemia severity assessed by stress perfusion nuclear imaging.

Inclusion Criteria: post-MI patients. Both single and Dual chamber ICD recipient. implanted more than 3 months ago. Agree to give written informed consent. Exclusion Criteria: Less than 18 years of age. ICD implantation as a 'bridge' to heart transplantation. Stable antiarrhythmic medication over the last month prior to enrollment. Patients taking class I antiarrhythmic medication. A projected lifespan less than one year. Participation in another trial (during or within 90 days before the study). Use of supplemental n-3 fatty acids during the last 3 months. Women who are pregnant and of childbearing potential who do not use adequate contraception. Patients known to have a history of recent drug or alcohol abuse. 10) History or current intestinal or hepatic disease.